111 results on '"Baldassare J"'
Search Results
2. Inhaled nitric oxide for prevention of bronchopulmonary dysplasia in premature babies (EUNO): a randomised controlled trial
- Author
-
Mercier, Jc, Hummler, H, Durrmeyer, X, SANCHEZ LUNA, M, Carnielli, V, Field, D, Greenough, A, VAN OVERMEIER, B, Jonsson, B, Hallman, M, Baldassare, J, and Chiandetti, Lino
- Subjects
Settore MED/38 - PEDIATRIA GENERALE E SPECIALISTICA ,Inhaled Nitric Oxide - Published
- 2010
3. Physical Studies of Human Adult Hemoglobins A and Chesapeake and Their Implication to the Nature of Oxygenation of Hemoglobin
- Author
-
Ho, Chien, primary, Mock, Nancy H., additional, Baldassare, J. J., additional, Davis, D. G., additional, Lindstrom, T. R., additional, Laman, Verna R., additional, Subasic, J. F., additional, and Charache, S., additional
- Full Text
- View/download PDF
4. Killing two birds with one RKIP
- Author
-
GOEL, R, primary and BALDASSARE, J, additional
- Published
- 2004
- Full Text
- View/download PDF
5. IL-1 activates the MAP kinase family of enzymes in human myometrial cells: Evidence for the involvement of p38 kinase in IL-1-induced cyclooxygenase-2 (Cox-2) expression
- Author
-
BELT, A, primary, BALDASSARE, J, additional, ROMERO, R, additional, and HERTELENDY, F, additional
- Published
- 1998
- Full Text
- View/download PDF
6. Interception of IL-1 signaling pathway by dexamethasone in Immortalized Human Myometrial Cells (IHMC)
- Author
-
HERTELENDY, F, primary, BELT, A, additional, BALDASSARE, J, additional, and ROMERO, R, additional
- Published
- 1998
- Full Text
- View/download PDF
7. Parathyroid hormone increases the expression of receptors for epidermal growth factor in UMR 106-01 cells.
- Author
-
Drake, M T, primary, Baldassare, J J, additional, McConkey, C L, additional, Gonzalez, E A, additional, and Martin, K J, additional
- Published
- 1994
- Full Text
- View/download PDF
8. Effect of U-73,122, an inhibitor of phospholipase C, on actions of parathyroid hormone in opossum kidney cells
- Author
-
Martin, K. J., primary, McConkey, C. L., additional, Jacob, A. K., additional, Gonzalez, E. A., additional, Khan, M., additional, and Baldassare, J. J., additional
- Published
- 1994
- Full Text
- View/download PDF
9. Effect of triamcinolone on parathyroid hormone-stimulated second messenger systems and phosphate transport in opossum kidney cells.
- Author
-
Martin, K J, primary, McConkey, C L, additional, Baldassare, J J, additional, and Jacob, A K, additional
- Published
- 1994
- Full Text
- View/download PDF
10. Differential induction of phosphatidylcholine hydrolysis, diacylglycerol formation and protein kinase C activation by epidermal growth factor and transforming growth factor-α in normal human skin fibroblasts and keratinocytes
- Author
-
Reynolds, N J, primary, Talwar, H S, additional, Baldassare, J J, additional, Henderson, P A, additional, Elder, J T, additional, Voorhees, J J, additional, and Fisher, G J, additional
- Published
- 1993
- Full Text
- View/download PDF
11. Reconstitution of thromboxane A2 receptor-stimulated phosphoinositide hydrolysis in isolated platelet membranes: involvement of phosphoinositide-specific phospholipase C-β and GTP-binding protein Gq
- Author
-
Baldassare, J J, primary, Tarver, A P, additional, Henderson, P A, additional, Mackin, W M, additional, Sahagan, B, additional, and Fisher, G J, additional
- Published
- 1993
- Full Text
- View/download PDF
12. Retinoic acid and phorbol ester synergistically up-regulate IL-8 expression and specifically modulate protein kinase C-epsilon in human skin fibroblasts.
- Author
-
Zhang, Q Y, primary, Hammerberg, C, additional, Baldassare, J J, additional, Henderson, P A, additional, Burns, D, additional, Ceska, M, additional, Voorhees, J J, additional, and Fisher, G J, additional
- Published
- 1992
- Full Text
- View/download PDF
13. The chemotactic activity of type I collagen for peripheral monocytes is present in CNBr fragments
- Author
-
Malone, J.D., primary, Richards, M., additional, and Baldassare, J., additional
- Published
- 1992
- Full Text
- View/download PDF
14. Molecular species analysis of mitogen-stimulated 1,2-diglycerides in fibroblasts. Comparison of alpha-thrombin, epidermal growth factor, and platelet-derived growth factor.
- Author
-
Pessin, M S, primary, Baldassare, J J, additional, and Raben, D M, additional
- Published
- 1990
- Full Text
- View/download PDF
15. The nuclear transcription factor NF-kappaB mediates interleukin-1beta-induced expression of cyclooxygenase-2 in human myometrial cells.
- Author
-
Belt, Andrew R., Baldassare, Joseph J., Belt, A R, Baldassare, J J, Molnár, M, Romero, R, and Hertelendy, F
- Subjects
TRANSCRIPTION factors ,INTERLEUKIN-1 ,PROSTAGLANDINS - Abstract
Objective: Up-regulation of prostaglandin production by gestational tissues in the setting of intrauterine infection has been implicated as an important contributor to preterm labor and parturition. In this study we investigated the possible role of the nuclear transcription factor NF-kappaB in interleukin-1 signaling, leading to the expression of cyclooxygenase 2 and prostaglandin production in human myometrial cell cultures.Study Design: Human myometrial smooth muscle cells from an immortalized line were used as a model system between passages 20 and 35. Growth-arrested cell cultures were stimulated with human recombinant interleukin 1, and the activation of NF-kappaB was assessed by the degradation of the inhibitory protein IkappaB-alpha (Western analysis), as well as by nuclear binding of NF-kappaB by using an electrophoretic mobility shift assay. The abundance of cyclooxygenase-2 messenger ribonucleic acid and protein was measured by Northern and Western analyses, whereas prostaglandin (prostaglandin I(2 ) and prostaglandin E(2 )) production was determined by specific radioimmunoassays.Results: Within 15 minutes of stimulation with interleukin 1, 90% of IkappaB-alpha was degraded. This was temporally associated with nuclear translocation and binding of NF-kappaB. Within 30 minutes, cyclooxygenase 2 messenger ribonucleic acid appeared, with steady-state levels increasing up to 4 hours. This was followed by an up to 80-fold increase in cyclooxygenase 2 protein and a corresponding time-dependent increase in prostaglandin production. When IkappaB-alpha degradation was blocked with calpain I inhibitor, NF-kappaB translocation, cyclooxygenase 2 messenger ribonucleic acid and protein expression, and prostaglandin synthesis were also inhibited.Conclusion: Stimulation of human myometrial cells with interleukin 1 leads to rapid activation of the transcription factor NF-kappaB, which is functionally linked to the expression of cyclooxygenase 2 messenger ribonucleic acid, protein, and prostaglandin synthesis. [ABSTRACT FROM AUTHOR]- Published
- 1999
- Full Text
- View/download PDF
16. MAGNETIC RESONANCE STUDIES OF HUMAN HEMOGLOBINS AND THEIR IMPLICATIONS TO THE STRUCTURE-FUNCTION RELATIONSHIPS IN HUMAN NORMAL AND ABNORMAL HEMOGLOBINS *.
- Author
-
Ho, C., Lindstrom, T. R., Baldassare, J. J., and Breen, J. J.
- Published
- 1973
- Full Text
- View/download PDF
17. Phospholipid metabolism and nuclear envelope signaling
- Author
-
Raben, D. M. and Baldassare, J. J.
- Published
- 2000
- Full Text
- View/download PDF
18. RhoA stimulates p27(Kip) degradation through its regulation of cyclin E/CDK2 activity.
- Author
-
Hu, W, Bellone, C J, and Baldassare, J J
- Abstract
RhoA has been identified as an important regulator of cell proliferation. We recently showed that the Ras/RhoA pathway regulates the degradation of p27(Kip) and the progression of Chinese hamster embryo fibroblasts (IIC9 cells) through G1 into S phase (Weber, J. D., Hu, W., Jefcoat, S. C., Raben, D. M., and Baldassare, J. J. (1997) J. Biol. Chem. 272, 32966-32971). In this report, we have demonstrated that, in IIC9 cells, RhoA regulates cyclin E/CDK2 activity, which is required for p27(Kip) degradation. As previously shown in several fibroblasts cell lines, expression of dominant-negative CDK2 in IIC9 cells blocked serum-induced cyclin E/CDK2 activity and p27(Kip) degradation. In the absence of serum, expression of constitutively active RhoA(63) resulted in significant stimulation of cyclin E/CDK2 activity and degradation of p27(Kip). Cotransfection of dominant-negative CDK2 and RhoA(63) inhibited RhoA(63)-induced cyclin E/CDK2 activity and p27(Kip) degradation. In addition, expression of dominant-negative RhoA blocked serum-induced cyclin E/CDK2 activity and p27(Kip) degradation. Finally, expression of catalytically active cyclin E/CDK2 rescued the effect of expression of dominant-negative RhoA. Taken together, these data show that RhoA regulates p27(Kip) degradation through its regulation of cyclin E/CDK2 activity.
- Published
- 1999
19. Alternate sources and substitutes for therapeutic blood components
- Author
-
Kahn, RA, Allen, RW, and Baldassare, J
- Published
- 1985
- Full Text
- View/download PDF
20. Ablation of Goalpha overrides G1 restriction point control through Ras/ERK/cyclin D1-CDK activities.
- Author
-
Weber, J D, Cheng, J, Raben, D M, Gardner, A, and Baldassare, J J
- Abstract
We have generated stable IIC9 cell lines, Goa1 and Goa2, that overexpress full-length antisense Goalpha RNA. As shown previously, expression of antisense Goalpha RNA ablated the alpha subunit of the heterotrimeric G protein, Go, resulting in growth in the absence of mitogen. To better understand this change in IIC9 phenotype, we have characterized the signaling pathway and cell cycle events previously shown to be important in control of IIC9 G1/S phase progression. In this paper we clearly demonstrate that ablation of Goalpha results in growth, constitutively active Ras/ERK, elevated expression of cyclin D1, and constitutively active cyclin D1-CDK complexes, all in the absence of mitogen. Furthermore, these characteristics were abolished by the transient overexpression of the transducin heterotrimeric G protein alpha subunit strongly suggesting the transformation of Goalpha-ablated cells involves Gobetagamma subunits. This is the first study to implicate a heterotrimeric G protein in tumor suppression.
- Published
- 1997
21. Ablation of Go alpha-subunit results in a transformed phenotype and constitutively active phosphatidylcholine-specific phospholipase C.
- Author
-
Cheng, J, Weber, J D, Baldassare, J J, and Raben, D M
- Abstract
Modulation of the components involved in mitogenic signaling cascades is critical to the regulation of cell growth. GTP-binding proteins and the stimulation of phosphatidylcholine (PC) hydrolysis have been shown to play major roles in these cascades. One of the enzymes involved in PC hydrolysis, a PC-specific phospholipase C (PC-PLC) has received relatively little attention. In this paper we examined the role of a particular heterotrimeric GTP-binding protein, Go, in the regulation of cell growth and PC-PLC-mediated hydrolysis of PC in IIC9 fibroblasts. The Go alpha-subunit was ablated in IIC9 cells by stable expression of antisense RNA. These stably transfected cells acquired a transformed phenotype as indicated by: (a) the formation of multiple foci in monolayer cultures, (b) the acquisition of anchorage-independent growth in soft agar; and (c) an increased level of thymidine incorporation in the absence of added mitogens. These data implicate Goalpha as a novel tumor suppressor. Interestingly, PC-PLC activity was constitutively active in the Goalpha-ablated cells as evidenced by the chronically elevated levels of diacylglycerol and phosphorylcholine in the absence of growth factors. In contrast, basal activities of PC-phospholipase D, phospholipase A2, or phosphoinositol-PLC were not affected. These data demonstrate, for the first time, a role for Go in regulating cell growth and provide definitive evidence for the existence of a PC-PLC in eukaryotic cells. The data further indicate that a subunit of Go, is involved in regulating this enzyme.
- Published
- 1997
22. Ras-stimulated extracellular signal-related kinase 1 and RhoA activities coordinate platelet-derived growth factor-induced G1 progression through the independent regulation of cyclin D1 and p27.
- Author
-
Weber, J D, Hu, W, Jefcoat, S C, Raben, D M, and Baldassare, J J
- Abstract
Platelet-derived growth factor (PDGF)-induced Ras activation is required for G1 progression in Chinese hamster embryo fibroblasts (IIC9 cells). Ras stimulates both extracellular signal-related kinase (ERK) activation and RhoA activation in response to PDGF stimulation. Inhibition of either of these Ras-stimulated pathways results in growth arrest. We have shown previously that Ras-stimulated ERK activation is essential for the induction and continued G1 expression of cyclin D1. In this study we examine the role of Ras-induced RhoA activity in G1 progression. Unstimulated IIC9 cells expressed high levels of the G1 cyclin-dependent kinase inhibitor p27(KIP1). Stimulation with PDGF resulted in a dramatic decrease in p27(KIP1) protein expression. This decrease was attributed to increased p27(KIP1) protein degradation. Overexpression of dominant-negative forms of Ras or RhoA completely blocked PDGF-induced p27(KIP1) degradation, but only dominant-negative Ras inhibited cyclin D1 protein expression. C3 transferase also inhibited PDGF-induced p27(KIP1) degradation, thus further implicating RhoA in p27(KIP1) regulation. Overexpression of dominant-negative ERK resulted in inhibition of PDGF-induced cyclin D1 expression but had no effect on PDGF-induced p27(KIP1) degradation. These data suggest that Ras coordinates the independent regulation of cyclin D1 and p27(KIP1) expression by the respective activation of ERK and RhoA and that these pathways converge to determine the activation state of complexes of cyclin D1 and cyclin-dependent kinase in response to mitogen.
- Published
- 1997
23. Biosynthesis of sulfidopeptide leukotrienes via the transfer of leukotriene A4 from polymorphonuclear cells to bovine retinal pericytes.
- Author
-
L, Mcmurdo, H, Stephenson A, J, Baldassare J, S, Sprague R, and J, Lonigro A
- Abstract
Administration of exogenous sulfidopeptide leukotrienes (LTs) is associated with enhanced microvascular permeability. In addition, endogenous LTs have been implicated as participants in permeability (nonhydrostatic) edema formation. The source of LTs for interaction with the microvasculature is, however, unknown. We hypothesized that pericytes contribute to vascular LT synthesis. Under basal conditions and after incubation with either the calcium ionophore, A23187 (0-1 microM), or arachidonic acid (20 microM), bovine retinal pericytes (BRPs) did not produce significant amounts of sulfidopeptide LTs. In contrast, in the presence of polymorphonuclear leukocytes (PMNs), which can synthesize LTA4, but not sulfidopeptide leukotrienes, incubation of BRPs with A23187 resulted in dose-dependent increases in LTC4/D4/E4 production (peak: 35.4 +/- 5 pg/microg protein; n = 12). Similarly, BRPs, incubated with exogenous, authentic LTA4 (10 microM), synthesized sulfidopeptide LTs (peak: 18.9 +/- 5 pg/microg protein, n = 3). Preincubation (30 min) of BRPs with PMNs and the lipoxygenase inhibitor, esculetin (1 x 10(-)4 M; n = 12), reduced peak A23187-induced production of LTs by 63.9 +/- 7%. Finally, Northern blot analysis revealed mRNA for 5-lipoxygenase to be present in human and bovine PMNs, but not in BRPs. These results suggest that pericytes produce sulfidopeptide LTs only when provided with LTA4 from an external source such as the PMN. Interactions between pericytes and PMNs may lead to the production of sulfidopeptide LTs, which, in turn, could alter microvascular permeability.
- Published
- 1998
24. Inhibition of fibrinogen receptor expression and serotonin release by leupeptin and antipain.
- Author
-
Baldassare, J J, Bakshian, S, Knipp, M A, and Fisher, G J
- Abstract
Human platelet agonists such as thrombin, ADP, and collagen stimulate the rapid expression of fibrinogen receptors. In other cell types, calcium-activated proteases have been suggested to participate in the mechanism of expression of cell surface receptors (Lynch, G., and Baudry, M. (1984) Science 224, 1057-1063). In platelets the majority of the neutral protease activity is calcium-activated protease. We examined the effects of leupeptin and antipain, two calcium-activated protease inhibitors, on the expression of platelet fibrinogen receptors. These inhibitors abolished thrombin and ADP-induced fibrinogen binding. This inhibition required the addition of leupeptin or antipain prior to the agonist and was not due to displacement of fibrinogen from its receptor or inhibition of agonist binding to platelets. Leupeptin and antipain also inhibited fibrinogen-independent thrombin-stimulated release of serotonin. These results are discussed in relation to the involvement of calcium-activated protease in early events of platelet activation.
- Published
- 1985
- Full Text
- View/download PDF
25. Enhancement of the reconstituted glucose transport activity from LM cells by phosphatidylethanolamine.
- Author
-
Baldassare, J J
- Abstract
The glucose transport activity from LM cells was solubilized with sodium cholate and reconstituted into liposomes containing phospholipids of varied polar head group composition. The reconstituted vesicles exhibited time-dependent preferential uptake of D- versus L-glucose. Phloretin and mercuric chloride, known inhibitors of glucose transport in the intact cells, inhibited the reconstituted transport activity. The transport activity was found to be sensitive to the phospholipid composition of the reconstituted vesicles. Proteoliposomes containing phosphatidylethanolamine showed increased transport activity. In addition, incubation of reconstituted vesicles containing phosphatidylcholine with phospholipase D plus ethanolamine resulted in vesicles containing phosphatidylcholine plus phosphatidylethanolamine and increased transport activity. These results indicate that the glucose transport system of LM cells is sensitive to polar head group structure of the phospholipids.
- Published
- 1983
- Full Text
- View/download PDF
26. Nuclear translocation of RhoA mediates the mitogen-induced activation of phospholipase D involved in nuclear envelope signal transduction.
- Author
-
Baldassare, J J, Jarpe, M B, Alferes, L, and Raben, D M
- Abstract
In this paper we demonstrate for the first time a mitogen-induced activation of a nuclear acting phosphatidylcholine-phospholipase D (PLD) which is mediated, at least in part, by the translocation of RhoA to the nucleus. Addition of alpha-thrombin to quiescent IIC9 cells results in an increase in PLD activity in IIC9 nuclei. This is indicated by an increase in the alpha-thrombin-induced production of nuclear phosphatidylethanol in quiescent cells incubated in the presence of ethanol as well as an increase in PLD activity in isolated nuclei. Consistent with our previous report (Wright, T. M., Willenberger, S., and Raben, D. M. (1992) Biochem. J. 285, 395-400), the presence of ethanol decreases the alpha-thrombin-induced production of phosphatidic acid without affecting the induced increase in nuclear diglyceride, indicating that the increase in nuclear PLD activity is responsible for the effect on phosphatidic acid, but not that on diglyceride. Our data further demonstrate that RhoA mediates the activation of nuclear PLD. RhoA translocates to the nucleus in response to alpha-thrombin. Additionally, PLD activity in nuclei isolated from alpha-thrombin-treated cells is reduced in a concentration-dependent fashion by incubation with RhoGDI and restored by the addition of prenylated RhoA in the presence of guanosine 5'-3-O-(thio)triphosphate. Western blot analysis indicates that this RhoGDI treatment results in the extraction of RhoA from the nuclear envelope. These data support a role for a RhoA-mediated activation of PLD in our recently described hypothesis, which proposes that a signal transduction cascade exists in the nuclear envelope and represents a novel signal transduction cascade that we have termed NEST (nuclear envelope signal transduction).
- Published
- 1997
27. Association of messenger ribonucleic acid with 70S monosomes from down-shifted Escherichia coli
- Author
-
Jacobson, L A and Baldassare, J C
- Abstract
The complexed 70S ribosomes (monosomes) that accumulate in Escherichia coli after an energy source shift-down were examined in an electron microscope. In all cases, the ribosomes lie at or near one end of a ribonucleic acid (RNA) strand. This messenger RNA (mRNA) has a mean length of 168 nm and a length-average length of 200 nm, sufficient to code for polypeptides of a weight-average molecular weight of 20,000. The length distribution indicates that these strands are a reasonable representation of the population of monocistronic mRNA's of E. coli. The mRNA strands disappear entirely upon digestion with pancreatic ribonuclease, phosphodiesterase I, or polynucleotide phosphorylase. The susceptibility to digestion by 3'-exonucleases indicate that the ribosomes lie at the 5' end of the mRNA strands. These results are consistent with the hypothesis that down-shifted cells have a translational defect at a point subsequent to the binding of ribosomes to mRNA but prior to the formation of the first peptide bond, such that ribosomes remain bound at or near their points of initial attachment to mRNA.
- Published
- 1976
- Full Text
- View/download PDF
28. Regulation of membrane-associated and cytosolic phospholipase C activities in human platelets by guanosine triphosphate.
- Author
-
Baldassare, J J, primary and Fisher, G J, additional
- Published
- 1986
- Full Text
- View/download PDF
29. Reconstruction of platelet proteins into phospholipid vesicles. Functional proteoliposomes.
- Author
-
Baldassare, J J, primary, Kahn, R A, additional, Knipp, M A, additional, and Newman, P J, additional
- Published
- 1985
- Full Text
- View/download PDF
30. Direct intra-tumoral injection of zinc-acetate halts tumor growth in a xenograft model of prostate cancer
- Author
-
Shah Maulik R, Kriedt Christopher L, Lents Nathan H, Hoyer Mary K, Jamaluddin Nimah, Klein Claudette, and Baldassare Joseph
- Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Intracellular levels of zinc have shown a strong inverse correlation to growth and malignancy of prostate cancer. To date, studies of zinc supplementation in prostate cancer have been equivocal and have not accounted for bioavailability of zinc. Therefore, we hypothesized that direct intra-tumoral injection of zinc could impact prostate cancer growth. In this study, we evaluated the cytotoxic properties of the pH neutral salt zinc acetate on the prostate cancer cell lines PC3, DU145 and LNCaP. Zinc acetate killed prostate cancer cell lines in vitro, independent of androgen sensitivity, in a dose-dependent manner in a range between 200 and 600 μM. Cell death occurred rapidly with 50% cell death by six hours and maximal cell death by 18 hours. We next established a xenograft model of prostate cancer and tested an experimental treatment protocol of direct intra-tumoral injection of zinc acetate. We found that zinc treatments halted the growth of the prostate cancer tumors and substantially extended the survival of the animals, whilst causing no detectable cytoxicity to other tissues. Thus, our studies form a solid proof-of-concept that direct intra-tumoral injection of zinc acetate could be a safe and effective treatment strategy for prostate cancer.
- Published
- 2009
- Full Text
- View/download PDF
31. Zinc is a potential therapeutic for chemoresistant ovarian cancer.
- Author
-
Bastow M, Kriedt CL, Baldassare J, Shah M, and Klein C
- Subjects
- Antibiotics, Antineoplastic pharmacology, Antineoplastic Agents, Phytogenic pharmacology, Cell Death drug effects, Cell Line, Tumor, Cisplatin pharmacology, Cyclin A drug effects, Cyclin A metabolism, Cyclin D drug effects, Cyclin D metabolism, Cyclin E drug effects, Cyclin E metabolism, Dose-Response Relationship, Drug, Doxorubicin pharmacology, Drug Synergism, Female, Humans, Paclitaxel pharmacology, Pyridines pharmacology, Thiones pharmacology, Cell Cycle Checkpoints drug effects, Ovarian Neoplasms drug therapy, Trace Elements pharmacology, Zinc pharmacology
- Abstract
Ovarian cancer is the leading cause of death from gynecological cancer. The high mortality rate reflets the lack of early diagnosis and limited treatment alternatives. We have observed a number of properties of zinc cytotoxicity that make it attractive from a therapeutic standpoint. Using SKOV3 and ES2 cells, ovarian cancer cell lines that demonstrate varied degrees of resistance to known therapeutics, we show that zinc killing is time and concentration dependent. Death is preceded by distinct changes in cell shape and size. The effects of zinc are additive with cisplatin or doxorubicin, whose morphological effects are distinct from those of zinc. Cytotoxicity of paclitaxel is minimal, making it difficult to determine additivity with zinc. Paclitaxel results in changes in cell shape and size similar to those of zinc but has different effects on cell cycle progression and cyclin expression. The data indicate that the means by which zinc kills ovarian cancer cells is distinct from currently used chemotherapeutics. Based on the properties reported here, zinc has the potential to be developed as either a primary treatment or as a second line of defense against cancers that have developed resistance to currently used chemotherapeutics.
- Published
- 2011
32. Zinc functions as a cytotoxic agent for prostate cancer cells independent of culture and growth conditions.
- Author
-
Kriedt CL, Baldassare J, Shah M, and Klein C
- Subjects
- Cell Line, Tumor, Cell Proliferation drug effects, Dose-Response Relationship, Drug, Extracellular Matrix physiology, Humans, Male, Prostatic Neoplasms pathology, Prostatic Neoplasms drug therapy, Zinc Sulfate pharmacology
- Abstract
The effects of zinc on the viability of PC3, LNCaP and DU145 prostate cancer cell lines in vitro were examined. The data indicate that, despite their distinctly different gene expression profiles, morphology and tissue origin, all cell lines responded to zinc in a similar time and dose dependent manner. Experiments using pyrithione indicated that cell death is mediated by internalized zinc. Zinc effects on cells plated as monolayers were compared to its effects on cells plated in a collagen matrix. Although the rate of cell growth in the matrix was delayed compared to cells in 2-dimensional cultures, the cytotoxic effects of zinc were unaltered. Using both 2-dimensional and 3-dimensional cultures, we observed that zinc cytotoxicity was independent of both the culture conditions and the rate of cell growth, results that contrast the activity of the current chemotherapeutics used to treat prostate cancer. The attractive properties of zinc cytotoxicity demonstrated in this paper suggest that is can be developed as a novel and effective chemotherapeutic agent for prostate cancer treatment.
- Published
- 2010
33. Molecular scaffold protein and cellular responses.
- Author
-
Keenan SM and Baldassare JJ
- Subjects
- Animals, Enzyme Activation, Heterotrimeric GTP-Binding Proteins metabolism, Receptors, Cell Surface metabolism, Saccharomyces cerevisiae enzymology, Saccharomyces cerevisiae metabolism, beta-Arrestins, Arrestins metabolism, MAP Kinase Signaling System, Mitogen-Activated Protein Kinases metabolism
- Abstract
Mitogen-activated kinases (MAPK) regulate many diverse cellular processes, including growth, differentiation and responses to stress. The organization of MAPKs through the use of scaffolding proteins is crucial for the selective activation of these kinases by different stimuli. Recent studies identify beta-arrestins as members of the family of MAPK scaffold proteins. beta-Arrestins not only shut off signaling by uncoupling G-protein-coupled receptors (GPCRs) from their heterotrimeric G proteins, but also contribute to the specificity of GPCRs signaling by recruiting and activating selective MAPKs.
- Published
- 2001
- Full Text
- View/download PDF
34. Nuclear diacylglycerol kinase-theta is activated in response to alpha-thrombin.
- Author
-
Bregoli L, Baldassare JJ, and Raben DM
- Subjects
- Active Transport, Cell Nucleus, Animals, Antibodies, Monoclonal immunology, Cell Line, Cricetinae, Diacylglycerol Kinase antagonists & inhibitors, Diacylglycerol Kinase immunology, Enzyme Activation, Fibroblasts drug effects, Fibroblasts enzymology, Models, Biological, Mutation, Phosphatidylserines pharmacology, rhoA GTP-Binding Protein genetics, Cell Nucleus enzymology, Diacylglycerol Kinase metabolism, Thrombin pharmacology
- Abstract
Currently, there is substantial evidence that nuclear lipid metabolism plays a critical role in a number of signal transduction cascades. Previous work from our laboratory showed that stimulation of quiescent fibroblasts with alpha-thrombin leads to the production of two lipid second messengers in the nucleus: an increase in nuclear diacylglycerol mass and an activation of phospholipase D, which catalyzes the hydrolysis of phosphatidylcholine to generate phosphatidic acid. Diacylglycerol kinase (DGK) catalyzes the conversion of diacylglycerol to phosphatidic acid, making it an attractive candidate for a signal transduction component. There is substantial evidence that this activity is indeed regulated in a number of signaling cascades (reviewed by van Blitterswijk, W. J., and Houssa, B. (1999) Chem. Phys. Lipids 98, 95-108). In this report, we show that the addition of alpha-thrombin to quiescent IIC9 fibroblasts results in an increase in nuclear DGK activity. The examination of nuclei isolated from quiescent IIC9 cells indicates that DGK-theta and DGK-delta are both present. We took advantage of the previous observations that phosphatidylserine inhibits DGK-delta (reviewed by Sakane, F., Imai, S., Kai, M., Wada, I., and Kanoh, H. (1996) J. Biol. Chem. 271, 8394-8401), and constitutively active RhoA inhibits DGK-theta (reviewed by Houssa, B., de Widt, J., Kranenburg, O., Moolenaar, W. H., and van Blitterswijk, W. J. (1999) J. Biol. Chem. 274, 6820-6822) to identify the activity induced by alpha-thrombin. Constitutively active RhoA inhibited the nuclear stimulated activity, whereas phosphatidylserine did not have an inhibitory effect. In addition, a monoclonal anti-DGK-theta antibody inhibited the alpha-thrombin-stimulated nuclear activity in vitro. These results demonstrate that DGK-theta is the isoform responsive to alpha-thrombin stimulation. Western blot and immunofluorescence microscopy analyses showed that alpha-thrombin induced the translocation of DGK-theta to the nucleus, implicating that this translocation is at least partly responsible for the increased nuclear activity. Taken together, these data are the first to demonstrate an agonist-induced activity of nuclear DGK-theta activity and a nuclear localization of DGK-delta.
- Published
- 2001
- Full Text
- View/download PDF
35. Cyclin-dependent kinase 2 nucleocytoplasmic translocation is regulated by extracellular regulated kinase.
- Author
-
Keenan SM, Bellone C, and Baldassare JJ
- Subjects
- Animals, Blotting, Western, Cell Division, Cell Line, Cricetinae, Cricetulus, Cyclin E metabolism, Cyclin-Dependent Kinase 2, Enzyme Induction, Immunohistochemistry, Phosphatidylinositol 3-Kinases biosynthesis, Phosphatidylinositol 3-Kinases metabolism, Precipitin Tests, Protein Transport, Thrombin pharmacology, CDC2-CDC28 Kinases, Cell Nucleus enzymology, Cyclin-Dependent Kinases metabolism, Cytoplasm enzymology, Mitogen-Activated Protein Kinases metabolism, Protein Serine-Threonine Kinases metabolism
- Abstract
Activation of cyclin-dependent kinase 2 (CDK2)-cyclin E in the late G(1) phase of the cell cycle is important for transit into S phase. In Chinese hamster embryonic fibroblasts (IIC9) phosphatidylinositol 3-kinase and ERK regulate alpha-thrombin-induced G(1) transit by their effects on cyclin D1 protein accumulation (Phillips-Mason, P. J., Raben, D. M., and Baldassare, J. J. (2000) J. Biol. Chem. 275, 18046-18053). Here, we show that ERK also affects CDK2-cyclin E activation by regulating the subcellular localization of CDK2. Ectopic expression of cyclin E rescues the inhibition of alpha-thrombin-induced activation of CDK2-cyclin E and transit into S phase brought about by treatment of IIC9 cells with LY29004, a selective inhibitor of mitogen stimulation of phosphatidylinositol 3-kinase activity. However, cyclin E expression is ineffectual in rescuing these effects when ERK activation is blocked by treatment with PD98059, a selective inhibitor of MEK activation of ERK. Investigation into the mechanistic reasons for this difference found the following. 1) Although treatment with LY29004 inhibits alpha-thrombin-stimulated nuclear localization, ectopic expression of cyclin E rescues CDK2 translocation. 2) In contrast to treatment with LY29004, ectopic expression of cyclin E fails to restore alpha-thrombin-stimulated nuclear CDK2 translocation in IIC9 cells treated with PD98059. 3) CDK2-cyclin E complexes are not affected by treatment with either inhibitor. These data indicate that, in addition to its effects on cyclin D1 expression, ERK activity is an important controller of the translocation of CDK2 into the nucleus where it is activated.
- Published
- 2001
- Full Text
- View/download PDF
36. PLD1b in IIC9 fibroblasts is selectively activated in the nucleus and not in the Golgi apparatus.
- Author
-
Baldassare JJ, Klaus J, Phillips PJ, and Raben DM
- Subjects
- ADP-Ribosylation Factors metabolism, Animals, Biological Transport, Cell Line, Cricetinae, Enzyme Activation, Hemostatics pharmacology, Phospholipase D genetics, Signal Transduction, Thrombin pharmacology, Transfection, Cell Nucleus enzymology, Fibroblasts enzymology, Golgi Apparatus enzymology, Phospholipase D metabolism
- Abstract
Mitogen-induced activation of a nuclear-acting PC-phospholipase D (PLD) is mediated, at least in part, by the translocation of RhoA to the nucleus. A remaining question is whether PLD in all subcellular compartments is regulated in the same manner. To address this question, we identified PLD in another subcellular compartment and determined whether its activity was influenced by alpha-thrombin in a RhoA-dependent manner. The data in this manuscript show that nuclear PLD is selectively regulated. alpha-Thrombin stimulates an increase in PLD activity in IIC9 fibroblast nuclei while Golgi PLD activity is unaffected. We cloned PLD1 from IIC9s (hamPLD1b) to show that it is present in both nuclei and Golgi. Interestingly, only nuclear PLD1 is modulated by alpha-thrombin, demonstrating that this activity is selectively regulated. These data provide support for the physiological importance of agonist-induced nuclear signalling enzymes., (Copyright 2001 Academic Press.)
- Published
- 2001
- Full Text
- View/download PDF
37. Phosphatidylinositol 3-kinase activity regulates alpha -thrombin-stimulated G1 progression by its effect on cyclin D1 expression and cyclin-dependent kinase 4 activity.
- Author
-
Phillips-Mason PJ, Raben DM, and Baldassare JJ
- Subjects
- Animals, Cells, Cultured, Chromones pharmacology, Cricetinae, Cricetulus, Cyclin-Dependent Kinase 4, DNA Replication, Enzyme Inhibitors pharmacology, Mitogen-Activated Protein Kinases metabolism, Morpholines pharmacology, Phosphoinositide-3 Kinase Inhibitors, Cyclin D1 biosynthesis, Cyclin-Dependent Kinases metabolism, G1 Phase, Phosphatidylinositol 3-Kinases metabolism, Proto-Oncogene Proteins, Thrombin metabolism
- Abstract
In this study, we present evidence that PI 3-kinase is required for alpha-thrombin-stimulated DNA synthesis in Chinese hamster embryonic fibroblasts (IIC9 cells). Previous results from our laboratory demonstrate that the mitogen-activated protein kinase (extracellular signal-regulated kinase (ERK)) pathway controls transit through G(1) phase of the cell cycle by regulating the induction of cyclin D1 mRNA levels and cyclin dependent kinase 4 (CDK4)-cyclin D1 activity. In IIC9 cells, PI 3-kinase activation also is an important controller of the expression of cyclin D1 protein and CDK4-cyclin D1 activity. Pretreatment of IIC9 cells with the selective PI 3-kinase inhibitor, LY294002 blocks the alpha-thrombin-stimulated increase in cyclin D1 protein and CDK4 activity. However, LY294002 does not affect alpha-thrombin-induced cyclin D1 steady state message levels, indicating that PI 3-kinase acts independent of the ERK pathway. Interestingly, expression of a dominant-negative Ras significantly decreased both alpha-thrombin-stimulated ERK and PI 3-kinase activities. These data clearly demonstrate that the alpha-thrombin-induced Ras activation coordinately regulates ERK and PI 3-kinase activities, both of which are required for expression of cyclin D1 protein and progression through G(1).
- Published
- 2000
- Full Text
- View/download PDF
38. Nuclear envelope signaling-role of phospholipid metabolism.
- Author
-
Raben DM and Baldassare JJ
- Subjects
- Animals, Cell Nucleus drug effects, Cell Nucleus metabolism, Cricetinae, Cricetulus, Diglycerides metabolism, Humans, Hydrolysis, Mitogens pharmacology, Phosphatidylcholines metabolism, Phosphatidylinositols metabolism, Receptor, PAR-1, Receptors, Thrombin metabolism, Nuclear Envelope metabolism, Phospholipids metabolism, Signal Transduction physiology
- Published
- 2000
39. The role of p38 mitogen-activated protein kinase in IL-1 beta transcription.
- Author
-
Baldassare JJ, Bi Y, and Bellone CJ
- Subjects
- Animals, CCAAT-Enhancer-Binding Protein-delta, Calcium-Calmodulin-Dependent Protein Kinases antagonists & inhibitors, Cell Line, Chloramphenicol O-Acetyltransferase antagonists & inhibitors, Chloramphenicol O-Acetyltransferase genetics, DNA-Binding Proteins antagonists & inhibitors, DNA-Binding Proteins genetics, Enzyme Activation drug effects, Enzyme Inhibitors pharmacology, Genes, Reporter drug effects, Imidazoles pharmacology, Interleukin-1 antagonists & inhibitors, Interleukin-1 metabolism, Interleukin-6 antagonists & inhibitors, Interleukin-6 genetics, Intracellular Fluid drug effects, Intracellular Fluid enzymology, Macrophages drug effects, Macrophages enzymology, Mice, Nuclear Proteins antagonists & inhibitors, Nuclear Proteins genetics, Protein Synthesis Inhibitors pharmacology, Pyridines pharmacology, RNA, Messenger antagonists & inhibitors, RNA, Messenger metabolism, Transcription, Genetic drug effects, p38 Mitogen-Activated Protein Kinases, CCAAT-Enhancer-Binding Proteins, Calcium-Calmodulin-Dependent Protein Kinases physiology, Interleukin-1 genetics, Mitogen-Activated Protein Kinases, Transcription Factors, Transcription, Genetic immunology
- Abstract
Several reports have shown that bicyclic imidazoles, specific inhibitors of the p38 mitogen-activated protein kinase (MAPK), block cytokine synthesis at the translational level. In this study, we examined the role of p38 MAPK in the regulation of the IL-1beta cytokine gene in monocytic cell lines using the bicyclic imidazole SB203580. Addition of SB203580 30 min before stimulation of monocytes with LPS inhibited IL-1beta protein and steady state message in a dose-dependent manner in both RAW264.7 and J774 cell lines. The loss of IL-1beta message was due mainly to inhibition of transcription, since nuclear run-off analysis showed an approximately 80% decrease in specific IL-1 RNA synthesis. In contrast, SB203580 had no effect on the synthesis of TNF-alpha message. LPS-stimulated p38 MAPK activity in the RAW264.7 cells was blocked by SB203580, as measured by the inhibition of MAPKAP2 kinase activity, a downstream target of the p38 MAPK. CCAATT/enhancer binding protein (C/EBP)/NFIL-6-driven chloramphenicol acetyltransferase (CAT) reporter activity was sensitive to SB203580, indicating that C/EBP/NFIL-6 transcription factor(s) are also targets of p38 MAPK. In contrast, transfected CAT constructs containing NF-kappaB elements were only partially inhibited (approximately 35%) at the highest concentration of SB203580 after LPS stimulation. As measured by EMSA, LPS-stimulated NF-kappaB activation was not affected by SB203580. Overall, the results demonstrate, for the first time, a role for p38 MAPK in IL-1beta transcription by acting through C/EBP/NFIL-6 transcription factors.
- Published
- 1999
40. Increased activation of Ras in psoriatic lesions.
- Author
-
Lin P, Baldassare JJ, Voorhees JJ, and Fisher GJ
- Subjects
- Animals, Cell Culture Techniques, Cricetinae, Embryo, Mammalian cytology, Female, Guanosine Diphosphate analysis, Guanosine Triphosphate analysis, Humans, Phosphotransferases physiology, Precipitin Tests, Pregnancy, Signal Transduction, Fibroblasts physiology, Psoriasis metabolism, Receptors, Growth Factor physiology, Skin growth & development, ras Proteins metabolism
- Abstract
Ras functions as an essential upstream regulator of growth-factor-receptor-coupled signal transduction pathways. Ras is converted from an inactive GDP-bound state to an active GTP-bound state in response to receptor activation. Thus, the ratio of GTP/GDP bound to Ras is a measure of its state of activation. Mutations that stabilize the GTP-bound form of Ras result in constitutive activation and cellular transformation. The most widely used method for measuring Ras activation utilizes [32P]PO4 to label cellular nucleotide pools and is therefore limited to use with cultured cells. We have modified and adapted an enzyme-based method for rapid, precise measurement of Ras-bound GTP and GDP in normal and psoriatic human skin. This method does not require radiolabeling of cellular nucleotides. In cultured fibroblasts, the enzymatic and [32P]PO4 incorporation methods yielded similar results. Application of the enzymatic method to human skin revealed that 6% of Ras was in the active GTP-bound state in normal skin, compared to 15.4% of Ras in psoriatic lesions. The total amount of Ras normalized to protein content was similar in normal and psoriatic skin. Enhanced activation of Ras is likely a critical mediator of the increased cell growth characteristic of psoriatic lesions.
- Published
- 1999
- Full Text
- View/download PDF
41. Dual coupling of the alpha-thrombin receptor to signal-transduction pathways involving phosphatidylinositol and phosphatidylcholine metabolism.
- Author
-
Cheng J, Baldassare JJ, and Raben DM
- Subjects
- Amino Acid Sequence, Animals, Arachidonic Acid metabolism, Base Sequence, Cricetinae, Cricetulus, DNA Primers, Enteropeptidase pharmacology, Hydrolysis, Mitosis, Oligopeptides pharmacology, Protein Binding, Phosphatidylcholines metabolism, Phosphatidylinositols metabolism, Receptors, Thrombin metabolism, Signal Transduction
- Abstract
Addition of alpha-thrombin to quiescent IIC9 cells results in the activation of lipid-metabolizing enzymes associated with signal-transduction cascades. These enzymes include phosphatidylinositol (PI)-specific phospholipase C (PI-PLC), phosphatidylcholine (PC)-specific phospholipases C and D and phospholipase A2 (PLA2). Whereas the alpha-thrombin receptor has been shown to couple with PI-PLCs, it is not clear whether this receptor, or a putative second receptor, couples to one or more of the other phospholipases. In this report we determine whether the cloned receptor couples to all or a subset of these enzymes. We show that (i) an alpha-thrombin-receptor-activating peptide also elicits the above responses and (ii) addition of enterokinase to IIC9 cells, stably transfected with an alpha-thrombin receptor (enterokinase- responsive alpha-thrombin receptor, EKTR) containing an enterokinase cleavage site in place of an alpha-thrombin cleavage site, stimulates both PI and PC hydrolysis, including PLA2. Enterokinase also induces mitogenesis in the IIC9s transfected with EKTR. These results indicate that, in addition to initiating a mitogenic signalling cascade, the cloned alpha-thrombin receptor couples to enzymes involved in generating PC-derived, as well as PI-derived, second-messenger molecules in IIC9s. Additionally, using the cells transfected with EKTR, we further demonstrate that only activated, i. e. cleaved, receptors are desensitized.
- Published
- 1999
42. Molecular aspects of Huntington's disease.
- Author
-
Walling HW, Baldassare JJ, and Westfall TC
- Subjects
- Animals, Brain metabolism, Brain pathology, Humans, Huntingtin Protein, Huntington Disease genetics, Huntington Disease pathology, Mice, Mice, Transgenic, Nerve Tissue Proteins chemistry, Nuclear Proteins chemistry, Peptides metabolism, Protein Binding, Ubiquitins metabolism, Huntington Disease metabolism, Nerve Tissue Proteins genetics, Nerve Tissue Proteins metabolism, Nuclear Proteins genetics, Nuclear Proteins metabolism
- Abstract
Huntington's disease (HD) is a progressive neurodegenerative disease striking principally medium spiny GABAergic neurons of the caudate nucleus of the basal ganglia. It affects about one in 10,000 individuals and is transmitted in an autosomal dominant fashion. The molecular basis of the disease is expansion of the trinucleotide CAG in the first exon of a gene on chromosome four. The CAG repeats are translated to polyglutamine repeats in the expressed protein, huntingtin. The normal function of huntingtin remains incompletely characterized, but based upon recently defined protein-protein interactions, it appears to be associated with the cytoskeleton and required for neurogenesis. Huntingtin has been demonstrated to interact with such proteins as HAP1, HIP1, microtubules, GADPH, calmodulin, and an ubiquitin-conjugating enzyme. Polyglutamine expansion alters many of these interactions and leads to huntingtin aggregation and the formation of neuronal nuclear inclusions, ultimately culminating in cell death. In this review, we discuss the molecular aspects of HD, including the present understanding of huntingtin-protein interactions, studies with transgenic mice, and postulated mechanisms of huntingtin aggregation.
- Published
- 1998
- Full Text
- View/download PDF
43. Adenovirus-mediated gene expression in isolated rat pancreatic acini and individual pancreatic acinar cells.
- Author
-
Padfield PJ, Elliott AC, and Baldassare JJ
- Subjects
- Amylases analysis, Amylases drug effects, Amylases metabolism, Animals, Cells, Cultured, Cholecystokinin pharmacology, Dose-Response Relationship, Drug, Exocytosis, Gene Transfer Techniques, Genetic Vectors, Models, Biological, Pancreas metabolism, Rats, Recombinant Proteins biosynthesis, Recombinant Proteins genetics, Transfection methods, Transgenes genetics, beta-Galactosidase analysis, beta-Galactosidase biosynthesis, beta-Galactosidase genetics, Adenoviridae genetics, Gene Expression genetics, Pancreas cytology
- Abstract
In this study we have examined the feasibility of using replication-deficient recombinant adenoviral vectors to transfer and express genes in pancreatic acinar cells in vitro. We infected primary cultures of both isolated pancreatic acini and individual acinar cells with a recombinant adenovirus containing the coding sequence for beta-galactosidase. Our data demonstrate that recombinant adenoviruses readily infect pancreatic acinar cells in vitro. Close to 100% infection and maximal beta-galactosidase expression were obtained, when acini or acinar cells were infected with 5x10(6) or 10(6) plaque-forming units (pfu) of virus per millitre of acini or acinar cell suspension, respectively. Examination of the time-course of beta-galactosidase expression showed that there was a lag of approximately 6 h before beta-galactosidase levels increased. Thereafter beta-galactosidase expression increased rapidly. By 20 h post-infection beta-galactosidase activity had increased from undetectable levels to 2.5-3.0 units/mg of cellular protein. Acini/acinar cells maintained a robust secretory response after adenoviral infection. The cholecystokinin-octapeptide (CCK8) dose/response curves for amylase secretion for acini and acinar cells infected with 5x10(5) and 1x10(5) pfu/ml of virus, respectively, were biphasic, with maximal amylase secretion being stimulated by 1 nM CCK8. In addition, the dose/response curves were identical to those obtained from control, sham-infected, acini/acinar cells. Our findings indicate that replication-deficient recombinant adenoviral vectors will be excellent tools to transfer and express genes in isolated pancreatic acini or acinar cells.
- Published
- 1998
- Full Text
- View/download PDF
44. Biosynthesis of sulfidopeptide leukotrienes via the transfer of leukotriene A4 from polymorphonuclear cells to bovine retinal pericytes.
- Author
-
Mcmurdo L, Stephenson AH, Baldassare JJ, Sprague RS, and Lonigro AJ
- Subjects
- Animals, Arachidonate 5-Lipoxygenase metabolism, Cattle, Cell Communication, Humans, Leukotriene A4 metabolism, Leukotrienes metabolism, Neutrophils enzymology, Leukotrienes biosynthesis, Neutrophils metabolism, Retina metabolism
- Abstract
Administration of exogenous sulfidopeptide leukotrienes (LTs) is associated with enhanced microvascular permeability. In addition, endogenous LTs have been implicated as participants in permeability (nonhydrostatic) edema formation. The source of LTs for interaction with the microvasculature is, however, unknown. We hypothesized that pericytes contribute to vascular LT synthesis. Under basal conditions and after incubation with either the calcium ionophore, A23187 (0-1 microM), or arachidonic acid (20 microM), bovine retinal pericytes (BRPs) did not produce significant amounts of sulfidopeptide LTs. In contrast, in the presence of polymorphonuclear leukocytes (PMNs), which can synthesize LTA4, but not sulfidopeptide leukotrienes, incubation of BRPs with A23187 resulted in dose-dependent increases in LTC4/D4/E4 production (peak: 35.4 +/- 5 pg/microg protein; n = 12). Similarly, BRPs, incubated with exogenous, authentic LTA4 (10 microM), synthesized sulfidopeptide LTs (peak: 18.9 +/- 5 pg/microg protein, n = 3). Preincubation (30 min) of BRPs with PMNs and the lipoxygenase inhibitor, esculetin (1 x 10(-)4 M; n = 12), reduced peak A23187-induced production of LTs by 63.9 +/- 7%. Finally, Northern blot analysis revealed mRNA for 5-lipoxygenase to be present in human and bovine PMNs, but not in BRPs. These results suggest that pericytes produce sulfidopeptide LTs only when provided with LTA4 from an external source such as the PMN. Interactions between pericytes and PMNs may lead to the production of sulfidopeptide LTs, which, in turn, could alter microvascular permeability.
- Published
- 1998
45. Fibronectin and cytokines increase JNK, ERK, AP-1 activity, and transin gene expression in rat hepatic stellate cells.
- Author
-
Poulos JE, Weber JD, Bellezzo JM, Di Bisceglie AM, Britton RS, Bacon BR, and Baldassare JJ
- Subjects
- Animals, Cells, Cultured, Chloramphenicol O-Acetyltransferase biosynthesis, Genes, Reporter, JNK Mitogen-Activated Protein Kinases, Liver cytology, Liver drug effects, Male, Rats, Rats, Sprague-Dawley, Tetradecanoylphorbol Acetate pharmacology, Transfection, Calcium-Calmodulin-Dependent Protein Kinases metabolism, Fibronectins pharmacology, Interleukin-1 pharmacology, Liver metabolism, Matrix Metalloproteinase 3 biosynthesis, Mitogen-Activated Protein Kinases, Transcription Factor AP-1 metabolism, Transcription, Genetic drug effects, Tumor Necrosis Factor-alpha pharmacology
- Abstract
Cytokines, growth factors, and alterations in the extracellular matrix composition may play a role in maintaining hepatic stellate cells (HSC) in the activated state that is responsible for hepatic fibrogenesis. However, the signal transduction pathways that are stimulated by these factors in HSC remain to be fully elucidated. Recent evidence indicates that the mitogen-activated protein kinase (MAPK) family, including c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK), plays an important role in the cellular response to stress. The aims of this study were to investigate whether fibronectin (FN) or the inflammatory cytokines interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) activate JNK, ERK, and AP-1 activity in HSC and induce the gene expression of the matrix metalloproteinase transin. Treatment of HSC with FN resulted in an up to 4.5-fold increase in ERK activity and a 2.1-fold increase in JNK activity. IL-1alpha and TNF-alpha produced up to a fourfold increase in JNK activity and a twofold increase in ERK activity. We then compared the effects of FN, IL-1alpha, and TNF-alpha on AP-1 activity and metalloproteinase mRNA induction. All three compounds increased AP-1 binding and promoter activity, and transin mRNA levels were increased 1.8-fold by FN, 2.2-fold by IL-1alpha, and 2.8-fold by TNF-alpha. Therefore, FN and inflammatory cytokines increase MAPK activity, stimulate AP-1 activity, and increase transin gene expression in HSC. Signal transduction pathways involving the MAPK family may play an important role in the regulation of matrix metalloproteinase expression by cytokines and FN in HSC.
- Published
- 1997
- Full Text
- View/download PDF
46. Sustained activation of extracellular-signal-regulated kinase 1 (ERK1) is required for the continued expression of cyclin D1 in G1 phase.
- Author
-
Weber JD, Raben DM, Phillips PJ, and Baldassare JJ
- Subjects
- Animals, Calcium-Calmodulin-Dependent Protein Kinases antagonists & inhibitors, Calcium-Calmodulin-Dependent Protein Kinases physiology, Cell Division drug effects, Cell Line, Cricetinae, Cricetulus, Enzyme Activation drug effects, Fibroblasts, Flavonoids pharmacology, JNK Mitogen-Activated Protein Kinases, Mitogen-Activated Protein Kinase 3, Platelet-Derived Growth Factor pharmacology, Time Factors, Up-Regulation drug effects, Calcium-Calmodulin-Dependent Protein Kinases metabolism, Cyclin D1 biosynthesis, G1 Phase drug effects, Mitogen-Activated Protein Kinases
- Abstract
In Chinese hamster embryo fibroblasts (IIC9 cells), platelet-derived growth factor (PDGF) stimulated mitogen-activated protein kinase/extracellular-signal-regulated kinase (MAP kinase/ERK) activity, but not that of c-jun N-terminal kinase (JNK), and induced G1 phase progression. ERK1 activation was biphasic and was sustained throughout the G1 phase of the cell cycle. PDGF induced cyclin D1 protein and mRNA levels in a time-dependent manner. Inhibition of PDGF-induced ERK1 activity by the addition of a selective inhibitor of MEK1 (MAP kinase kinase/ERK kinase 1) activation, PD98059, or transfection with a dominant-negative ERK1 (dnERK-) was correlated with growth arrest. In contrast, growth was unaffected by expression of dominant-negative JNK (dnJNK-). Interestingly, addition of PD98059 or dnERK-, but not dnJNK-, resulted in a dramatic decrease in cyclin D1 protein and mRNA levels, concomitant with a decrease in cyclin D1-cyclin-dependent kinase activity. To investigate the importance of sustained ERK1 activation, ERK1 activity was blocked by the addition of PD98059 throughout G1. Addition of PD98059 up to 4 h after PDGF treatment decreased ERK1 activity to the levels found in growth-arrested IIC9 cells. Loss of cyclin D1 mRNA and protein expression was observed within 1 h after inhibition of the second sustained phase of ERK1 activity. Disruption of sustained ERK1 activity also resulted in G1 growth arrest. These data provide evidence for a role for sustained ERK activity in controlling G1 progression through positive regulation of the continued expression of cyclin D1, a protein known to positively regulate G1 progression.
- Published
- 1997
- Full Text
- View/download PDF
47. Thrombin activation of human platelets dissociates a complex containing gelsolin and actin from phosphatidylinositide-specific phospholipase Cgamma1.
- Author
-
Baldassare JJ, Henderson PA, Tarver A, and Fisher GJ
- Subjects
- Actins isolation & purification, Actins pharmacology, Blood Platelets drug effects, Electrophoresis, Polyacrylamide Gel, Gelsolin isolation & purification, Gelsolin pharmacology, Humans, In Vitro Techniques, Isoenzymes isolation & purification, Kinetics, Phospholipase C gamma, Platelet Activation, Platelet Aggregation, Type C Phospholipases isolation & purification, Actins blood, Blood Platelets physiology, Gelsolin blood, Isoenzymes blood, Thrombin pharmacology, Type C Phospholipases blood
- Abstract
We have examined the association of two cytoskeleton proteins, gelsolin and actin, with phosphatidylinositide-specific phospholipase Cgamma1 (PLCgamma1) in resting and thrombin-stimulated human platelets. In unstimulated platelets, gelsolin, actin and PLCgamma1 were immunoprecipitated as a complex by a polyclonal antibody to PLCgamma1. The association of gelsolin and actin was specific for PLCgamma1 because immunoprecipitates of PLCs beta2, beta3, gamma2 and delta1, which are also expressed in human platelets, did not contain detectable gelsolin or actin. Activation with thrombin resulted in platelet aggregation and the dissociation of gelsolin and actin from PLCgamma1. Inhibition of thrombin-induced platelet aggregation blocked the dissociation of gelsolin and actin from PLCgamma1. After stimulation with thrombin, PLCgamma1 activity in immunoprecipitates was increased 2-3-fold. This elevation in PLCgamma1 activity in response to thrombin activation was not observed when platelet aggregation was blocked. Although PLCgamma1 is tyrosine phosphorylated in response to many agonists, we could not detect, by Western analysis with anti-phosphotyrosine antibodies, tyrosine phosphorylation of PLCgamma1 immunoprecipitated from thrombin-stimulated platelets. These results demonstrate that PLCgamma1 is associated with gelsolin and actin in resting platelets, and that thrombin-induced platelet aggregation results in the dissociation of PLCgamma1 from gelsolin and actin, and the stimulation of PLCgamma1 activity.
- Published
- 1997
- Full Text
- View/download PDF
48. Effect of cytokines on prostaglandin E2 and prostacyclin production in primary cultures of human myometrial cells.
- Author
-
Todd HM, Dundoo VL, Gerber WR, Cwiak CA, Baldassare JJ, and Hertelendy F
- Subjects
- 6-Ketoprostaglandin F1 alpha biosynthesis, Analysis of Variance, Cells, Cultured, Cycloheximide pharmacology, Dactinomycin pharmacology, Drug Synergism, Female, Humans, Interleukin 1 Receptor Antagonist Protein, Interleukin-1 pharmacology, Interleukin-6 pharmacology, Interleukin-8 pharmacology, Myometrium cytology, Myometrium metabolism, Radioimmunoassay, Recombinant Proteins pharmacology, Sialoglycoproteins pharmacology, Tetradecanoylphorbol Acetate pharmacology, Transforming Growth Factor beta pharmacology, Dinoprostone biosynthesis, Epoprostenol biosynthesis, Interleukins pharmacology, Myometrium drug effects
- Abstract
The objective of this study was to characterize interleukin-1, -6, and -8 (IL-1-, IL-6-, and IL-8)-induced prostacyclin (PGI2 as 6-keto PGF1 alpha) and prostaglandin E2 (PGE2) production in primary cultures of human myometrial cells. Prostaglandins (PGs) released into the culture media were quantitated by specific radioimmunoassays. IL-1, but not IL-6 or IL-8, caused a dose- and time-dependent increase in the production of both PGI2 and PGE2. Half-maximally stimulating doses (EC50) of IL-1 were about 0.1 ng/ml, and maximal responses were observed at 1-10 ng/ml, amounting to 15- to 23-fold increases over unstimulated controls. The action of IL-1 was greatly potentiated by the protein kinase C-activating phorbol ester, TPA, and inhibited by actinomycin D and cycloheximide. IL-1-induced PG production was also suppressed by dexamethasone, by the natural IL-1 receptor antagonist (IL-1ra), and by transforming growth factor1 beta (TGF1 beta). It is concluded that IL-1 is a potent agonist of PG synthesis in human myometrial cells, acting by a mechanism dependent on the synthesis of new proteins, presumably key enzymes (phospholipase A2 and/or cyclo-oxygenase-2). This study has added further support to the notion that the myometrium serves as a target for the inflammatory cytokine, IL-1, and thereby may be affected directly, thus promoting preterm labor associated with intrauterine infection.
- Published
- 1996
- Full Text
- View/download PDF
49. Differential effects of G-protein activators on 5-hydroxytryptamine and platelet-derived growth factor release from streptolysin-O-permeabilized human platelets.
- Author
-
Padfield PJ, Panesar N, Henderson P, and Baldassare JJ
- Subjects
- Aluminum Compounds pharmacology, Bacterial Proteins, Blood Platelets drug effects, Calcium pharmacology, Cell Membrane Permeability, Cytoplasmic Granules drug effects, Cytoplasmic Granules metabolism, Diglycerides metabolism, Egtazic Acid pharmacology, Fluorides pharmacology, Guanosine 5'-O-(3-Thiotriphosphate) pharmacology, Humans, L-Lactate Dehydrogenase metabolism, Phosphatidic Acids metabolism, Streptolysins pharmacology, Blood Platelets metabolism, GTP-Binding Proteins metabolism, Platelet-Derived Growth Factor metabolism, Serotonin metabolism
- Abstract
In this paper we have used streptolysin O (SLO)-permeabilized human platelets to examine the G-protein(s) that control Ca2+-independent secretion from alpha and dense-core granules. As shown for electropermeabilized platelets, Ca2+ alone stimulated a concentration-dependent increase in 5-hydroxytryptamine (5-HT) (dense-core-granule marker) and platelet-derived growth factor (PDGF) (alpha-granule marker) release from the SLO-permeabilized cells. The EC50 values of Ca2+-dependent 5-HT and PDGF release were 5 microM and 10 microM respectively. Guanosine 5'-[gamma-thio]triphosphate (GTP[S]) (100 microM) stimulated Ca2+-independent release from both alpha and dense-core granules. In contrast, AlF4- had no effect on Ca2+-independent release from either alpha or dense-core granules. Neither GTP[S] nor AlF4- appeared to have a significant effect on Ca2+-dependent release from alpha and dense-core granules. GTP[S] can activate both heterotrimeric and low-molecular-mass G-proteins, whereas AlF4- activates only heterotrimeric G-proteins. Our results, therefore suggest that secretion in the human platelet is regulated by a small G-protein. Both GTP[S]- and Ca2+-dependent secretion were effected by extending the time between permeabilization with SLO and stimulation of secretion. GTP[S]-stimulated secretion from alpha and dense-core granules decreased rapidly after permeabilization. In contrast, Ca2+-dependent 5-HT and PDGF release ran down at a much lower rate. These observations indicate that GTP[S] and Ca2+ act through parallel pathways to stimulate secretion from SLO-permeabilized platelets.
- Published
- 1996
- Full Text
- View/download PDF
50. Cellular distribution of isoforms of protein kinase C (PKC) in pancreatic acini.
- Author
-
Bastani B, Yang L, Baldassare JJ, Pollo DA, and Gardner JD
- Subjects
- Animals, Cell Compartmentation, Cell Membrane enzymology, Diglycerides metabolism, Fluorescent Antibody Technique, Indirect, Pancreas cytology, Rats, Rats, Sprague-Dawley, Sincalide pharmacology, Tetradecanoylphorbol Acetate pharmacology, Isoenzymes metabolism, Pancreas enzymology, Protein Kinase C metabolism
- Abstract
As in a previous study (Biochim, Biophys. Acta 1224 (1994) 127-138), we used quantitative immunoblot analysis and found that rat pancreatic acini possess four different isoforms of PKC-alpha, delta, epsilon and zeta. The phorbol ester 12-O-tetradecanoyl phorbol 13-acetate (TPA) caused translocation of each isoform from the cytosol to the membrane fraction. CCK-8 increased diacylglycerol (DAG) and caused translocation of PKC-sigma and PKC-epsilon but not that of PKC-alpha or PKC-zeta. L-364,718, a CCK receptor antagonist, prevented as well as reversed the effects of CCK-8 on DAG and on translocation of PKC-sigma and PKC-epsilon. To explore the possibility that different isoforms of PKC might have different distributions in rat pancreas, we used immunocytochemistry to determine the cellular distribution of different isoforms of PKC in intact pancreas as well as pancreatic acini. In intact pancreas, PKC-alpha and PKC-sigma were detected in islet cells but not in duct or acinar cells. PKC-epsilon was detected in the apical region of acinar cells and PKC-zeta was detected over the luminal surfaces of acinar cells and the ductules that extend from the acinus. Neither PKC-epsilon nor PKC-zeta was detected in islets. In pancreatic acini PKC-alpha and PKC-sigma were detected in islets or fragments of islets that contaminated the preparation but were not detected in acinar cells. PKC-epsilon was detected in the apical region of acinar cells and adding 1 microM TPA or 1 microM CCK-8 accentuated the immunostaining but did not alter its cellular distribution. L-364,718 reversed the changes in immunostaining caused by CCK-8. PKC-zeta was detected over the luminal surface of the acinar cells. TPA, but not CCK-8 or CCK-8 followed by L-364,718, increased the number of acini that showed staining of the luminal surfaces of acinar cells. Thus, the present results demonstrate that different isoforms of PKC are distributed differently in rat pancreas and that the different patterns of distribution can explain, at least in part, the different responses to CCK-8.
- Published
- 1995
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.